Allow for larger codec private data

This change adds support for multibyte sizes in the ESDS. Previously the
Matroska extractor only supported single byte sizes, so codec private data
had to be less than 108 bytes, and would crash if it was bigger.
b/12584090

Change-Id: I9edfc2f687187d1e98bcfd2fe56576312435df3e
1 file changed